Panel, especially floor panel

ABSTRACT

A panel, in particular floor panel, with a core of wood material or a wood material/plastic mixture, a top side and a bottom side, which panel has on at least two opposite lateral edges a profiling corresponding to one another such that two identically embodied panels can be connected and locked to one another by an essentially vertical joining motion in the horizontal and vertical directions, wherein the locking in the vertical direction can be brought about by at least one tongue element movable in the horizontal direction, which element snaps into place during the joining motion behind a locking edge extending essentially in the horizontal direction, is characterized in that the tongue element is formed in one piece out of the core.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuing application of co pending U.S.application Ser No. 12/282,838, filed on Jan. 21, 2009, the contents ofwhich are incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The invention relates to a panel, in particular a floor panel, with acore made of wood material or a wood material/plastic mixture, a topside and a bottom side, which panel has on at least two opposite lateraledges a profiling corresponding to one another such that two identicallyembodied panels can be connected and locked to one another by anessentially vertical joining motion in the horizontal and verticaldirections, wherein the locking in the vertical direction can be broughtabout by at least one tongue element movable in the horizontaldirection, which element snaps into place during the joining motionbehind a locking edge extending essentially in the horizontal direction.

BACKGROUND OF INVENTION

A panel of this type is known, for example, from EP 1 650 375 A1. Thistype of locking implemented with this panel is preferably provided onthe transverse side of floor panels. But it can also be provided on thelongitudinal side or on both the longitudinal and the transverse sides.The tongue element is made of plastic and is inserted into a grooveextending horizontally on one of the lateral edges and is beveled on itstop side. Like a door latch, the bevel causes the tongue element to bepressed inward into the groove by the panel to be newly fitted when thebottom side of this panel touches the beveling and is lowered further.When the panel to be newly attached has been lowered completely to thetuider-floor, the tongue element snaps into a groove introducedhorizontally in the opposite lateral edge and locks the two panels inthe vertical direction. Special injection molding tools are required forthe manufacture of this tongue element, so that the production isrelatively expensive. Furthermore, a high-quality plastic has to be usedto provide adequate strength values, which makes the tongue element evenmore expensive. If plastics with insufficient strength values are used,this leads to relatively large dimensions of the tongue elements, sincethis is the only way to ensure that corresponding forces can be producedor transferred.

The fact that the locking element is embodied as a separate componentcauses additional expenses. For technological reasons the production ofthe locking element takes place in a location separate from the panels,so that an integration into the continuous production process, inparticular for floor panels, if anything is impossible. Because of thedifferent materials, wood material on the one hand and plastic on theother hand, it is complex and cost-intensive to match the manufacturingtolerances from two separate production processes. Since the locking inthe vertical direction would be ineffective if the locking element weremissing, this element must further be safeguarded from falling out ofthe groove introduced into the lateral edge during the furtherproduction process and during transport. This securing is also complex.As an alternative, the locking element could also be provided separatelyto the consumer.

With increasing frequency the floor panels under discussion are laid bydo-it-yourselfers, so that it is basically possible through a lack ofexperience for the required number of locking elements to be misjudgedat first and for them not to be procured in an amount sufficient tofinish a room. Furthermore, it cannot be ruled out that thedo-it-yourselfer may make a mistake when inserting the tongue element,which means that the locking is not possible in an exact manner andcauses the interconnection to release over time, which the consumer thenincorrectly attributes to the quality delivered by the producer.

From DE 102 24 540 A1 panels are known that are profiled on oppositelateral edges such that hook-shaped connecting elements form for lockingin the horizontal direction. For locking in the vertical direction, theconnecting elements are provided with form-fitting elements spaced apartfrom one another horizontally and vertically and with undercutscorresponding to them with one horizontally oriented locking surfaceeach. The transverse extension of horizontally oriented locking surfacesof this type is about 0.05 to 1.0 mm. The dimensioning must be so smallfor the joining of two panels to remain possible at all. But thisinevitably leads to the fact that only small, vertically directed forcescan be absorbed, so that extremely low tolerances must be used duringmanufacture to ensure that the connection does not spring open withnormal stress even in the case of minor floor unevenness and/or softundersurfaces.

SUMMARY OF INVENTION

Based on this problem, the panel described at the outset is to beimproved.

To solve the problem, a generic floor panel is characterized in that thetongue element is formed in one piece out of the core.

This embodiment drastically simplifies production. There is no matchingof tolerances of different components. Manufacture times and expensesare reduced, because it is not necessary to bring and keep togetherdifferent components. Furthermore, it is ensured that the end consumeris not missing any components and unable to continue his work.

Preferably, the at least one tongue element is free with respect to thecore in the direction of the top side and in the direction of theopposite lateral edge, and connected to the core on at least one end,particularly preferably on both ends, in the direction of its lateraledge. The tongue elasticity can be adjusted through the size of theeffective connection of the tongue element to the core.

The tongue element is preferably exposed by means of a horizontal and avertical slit. Not only does the width of the slits determine thestrength of the link of the tongue element to the core material, but thechoice of the width of the vertical slit also makes it possible tocreate a stop for the tongue element in the horizontal direction, sothat the tongue element is safely protected against overstretching.

If a plurality of tongue elements spaced apart from one another isprovided over the length of the lateral edge, the stability of theconnection is increased because the free spring deflection in thelongitudinal direction of the tongue element is limited. It is possibleto select the distance between the individual tongue elements to belarger or smaller. The smaller the distance, the larger naturally theeffective surface for locking, so that the transferable forces in thevertical direction are correspondingly high.

The horizontal locking preferably takes place by means of hook elementscorresponding to one another, the hook element on the lateral edgehaving the locking edge being embodied by a shoulder projecting in thedirection of the top side, and the hook element on the lateral edgehaving the tongue element being embodied by a shoulder directed in thedirection of the bottom side.

If the outer edge of the tongue element runs tilted at an angle to thetop side, the joining motion is facilitated because with increasingmotion the tongue element deflects deeper in the direction of the panelcore.

The locking edge running essentially horizontally is preferably thesidewall of a groove introduced into the lateral edge.

But the locking edge running essentially horizontally can also be formedby a projection protruding outward on the projecting shoulder. In thiscase it is then advantageous if the tongue element ends on the bottomside of the panel.

In order to achieve a safest possible locking in the vertical direction,the shoulder projecting downward can have an at least partially flat topsurface that ends in the same horizontal plane as a bearing surfaceembodied on the opposite lateral edge, so that two panels connected toone another can support each other.

If the hook elements are embodied such that there is a preload at thejoint of two panels connected to one another, the lateral edges of thepanels are pressed against one another with their vertical surfaces inthe area of the top side, through which a tight connection on the topside of the plate can be achieved and the formation of gaps can beprevented.

BRIEF DESCRIPTION O DRAWINGS

The following exemplary embodiments of the invention are described withthe aid of the following drawings.

FIG. 1 shows a top view of a first panel;

FIG. 2 shows a representation of two panels connected to one another inpart section analogous to the line of cut II-II according to FIG. 1;

FIG. 3 shows a representation corresponding to FIG. 2 analogous to theline of cut III-III according to FIG. 1;

FIG. 4 shows a first variation of the panel according to FIGS. 2 and 3;

FIG. 5 shows a second variation of the panel according to FIGS. 2 and 3;

FIG. 6 shows a side view of two panels connected to one anotheraccording to a second exemplary embodiment;

FIG. 7 shows a section of the panels connected to one another from FIG.6;

FIG. 8 shows a further embodiment of the panels; and

FIG. 9 shows a fourth embodiment of the panels.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The panels 1, 2 are embodied identically. They comprise a core 17 ofwood material or a wood material/plastic mixture. On their oppositelateral edges I, II the panels 1, 2 are profiled, the lateral edge Ibeing milled from the top side 18 and the lateral edge II being milledfrom the bottom side 19. The tongue element 3 is embodied on the lateraledge II, which element was produced by cutting free the core 17 in thata horizontal slit 11 and a slit 10 running essentially vertically weremilled. The lateral edges I, II have the length L. In the longitudinaldirection of the lateral edge II, the tongue element 3 is connected onits ends 3 a, 3 b to the core material. The exposure of the tongueelement 3 from the core 17 occurs through the slits 10, 11 only. Theouter edge 3 c of the tongue element 3 is tilted at the angle .alpha.with respect to the top side 18 of the panel 2. The vertical surfaces ofthe lateral edges I, II are machined such that mating surfaces 15, 16form in the area of the top side 18.

On the lateral edge I opposite the tongue element 3, the panel 1 isprovided with a groove 9 extending essentially in the horizontaldirection H, the upper sidewall of which groove embodies a locking edge4 running essentially horizontally. As shown in the figures, the groovebottom of the groove 9 runs parallel to the outer edge 3 c of the tongueelement 3, which facilitates the manufacture of the groove 9, but itcould also be made strictly in the vertical direction or at an angledeviating from the angle .alpha..

The locking of the two panels 1, 2 in the horizontal direction takesplace by means of the hook elements 20, 21 produced through a stepprofiling by milling, and in the vertical direction via the tongueelement 3 in connection with the locking edge 4 of the groove 9. On theshoulder 5, extending downward, of the hook element 21, an at leastpartially flat top surface 12 is embodied that interacts with a bearingsurface 13 embodied on the hook element 20 on the opposite lateral edgeI, which bearing surface projects backward behind the projection 6. Thetop surface 12 and the bearing surface 13 end in the same horizontalplane E, so that the panels 1, 2 connected to one another support eachother. The profiling of the hook elements 20, 21 is chosen such that apreload is created in the joint, and the vertical mating surfaces 15, 16of the panels 1, 2 are pressed against one another, so that there is novisible gap on the top side 18 of two panels 1, 2 connected to oneanother. In order to facilitate the joining of the panels 1, 2, theshoulder 6, projecting upward, of the hook element 20 and the shoulder5, projecting downward, of the hook element 21 are chamfered or roundedon their edges. In order to simplify the manufacture for embodying thetongue element 3, either the slit 11 running horizontally (FIG. 4) orthe slit 10 running essentially vertically (FIG. 5) can be continuous,i.e., extend over the full length L of the lateral edge II.

The panel 2 is connected to the panel 1 already lying on the under-floorin that the panel 2 is fitted to the lateral edge I of the panel 1 andlowered in the direction of the under-floor by an essentially verticaljoining motion. When the tongue element 3 with its lower edge 3 dadjoins the top side 18 of the panel 1, the tongue element is pressed inthe direction of the core 17 during the further joining motion when ittouches the mating surface 15 because of its outer lateral edge 3 crunning at the angle .alpha., so that the tongue element deflects in thehorizontal direction H. The panel 2 is further lowered downward. Whenthe tongue element 3 reaches a position opposite the groove 9, itsprings out as a result of the restoring forces inherent in the materialand then snaps into the groove 9, where it bears against the lockingedge 4 with its top side 3 e running essentially horizontally. At thesame time, the hook elements 20, 21 engage until the top surface 12 issupported on the bearing surface 13. The panels 1, 2 are then connectedand locked to each other. The inner wall 10 a of the slit 10 serves as alimitation of the spring deflection for the tongue element 3, in orderto prevent the pulling out of the connection between the tongue element3 on its ends 3 a, 3 b and the core 17 because of an excessively wideplunging motion. The surface, i.e., the height and the width with whichthe ends 3 a, 3 b are connected to the core 17 determines the springrate of the tongue element 3. As FIGS. 8 and 9 show, several tongueelements 3 can be embodied over the length L of the lateral edge II.FIGS. 8 and 9 show two embodied tongue elements 3. It is also easilyconceivable to embody the tongue elements 3 shorter and to provide five,six or even seven or more tongue elements 3.

In the exemplary embodiment shown in FIGS. 6 and 7, the tongue element 3is embodied on the bottom side 19 of the panels 1, 2. The locking edge 4on the lateral edge I is formed by a projection 8 on the shoulder 6.Here the exposure of the tongue element 3 also occurs through the slit11 running essentially in the horizontal direction H and the slit 10running in the vertical direction V. Here it is possible as well thatone of the slits 10, 11 extends over the full length L of the lateraledge II to simplify the manufacturing process. In this embodiment, thevertical surfaces 15, 16 are machined on the lateral edges I, II suchthat a dust pocket 14 forms, an undercut 7 projecting into the core 17being provided on the lateral edge I.

If the vertical slit 10 is embodied to be narrow enough, it is possibleto keep the tongue element 3 connected to the core by only one of itsends 3 a or 3 b. This is indicated in the top view according to FIG. 9.An embodiment of this type has the advantage that the tongue element 3can extend in the direction of the length L of the lateral edge II aswell. The end 3 a or 3 b which is then free is then supported on theinner wall 10 a of the slit 10.

With the panel 1, 2 displayed in FIGS. 2 and 3, the tongue element 3 isshaped by means of tools slidable crosswise to the processing direction.Milling tools, laser tools or water-jet tools or even upright blades orbroaches can be used as tools. With the exemplary embodiments accordingto FIGS. 4 and 5, only one slidable tool is required in each case, sothat the respectively other exposure can be carried out by means of aconventional stationary tool. The area that is not exposed, thatconnects the tongue element 3 to the core 17 in one piece, is therebyreduced. It is thus also possible to adjust locking forces of differentstrengths. With all of the exemplary embodiments the locking isdetachable by shifting the panels 1, 2 relatively to one another alongthe lateral edges I, II or by inserting a release pin (not shown)laterally into the joint.

The panels 1, 2 are customarily provided with a pattern on their topside 18, which pattern can be printed directly onto the top side 18. Thepattern is customarily covered by an antiabrasion layer, into which astructuring corresponding to the pattern can be embossed.

This type of locking described above is preferably provided on thetransverse side of panels 1, 2, which can be connected to one another ontheir longitudinal side by angling and pivoting downward onto theunder-floor, as described in DE 102 24 540 A1. It is also conceivable,however, to embody this profiling both on the longitudinal sides and thetransverse sides, so that the panels can be connected and locked to oneanother on all lateral edges by a purely vertical joining motion.

1. A method for producing a floor panel, with a core of wood material ora wood material/plastic mixture, a top and a bottom, which has on atleast two side edges (I, II) lying opposite one another a profilecorresponding to one another such that two panels embodied identicallycan be connected and locked to one another in a horizontal and verticaldirection by an essentially vertical joining movement, wherein thelocking in the vertical direction can be effected by at least one tongueelement formed in one piece from the core on the side edge (II) andmoveable in the horizontal direction, which tongue element during thejoining movement snaps in behind a locking edge extending essentially inthe horizontal direction, in that, by means of tools displaceabletransversely to a processing direction, the at least one tongue elementis exposed with respect to the core in the direction of the top and inthe direction of the side edge (I) lying opposite the top, and therebyremains connected to the core in the direction of its side edge (II) onat least one of its two ends.
 2. The method according to claim 1,wherein milling tools, laser tools or water-jet tools, upright blades orbroaches are used as tools.
 3. The method according to claim 2, whereinthe tongue element remains connected at both of its ends to the core. 4.The method according to claim 1, wherein the tongue element remainsconnected at both of its ends to the core.
 5. The method according toclaim 1 wherein the tongue element is exposed with respect to the coreby means of an essentially horizontal slot and an essentially verticalslot.
 6. The method according to claim 1, wherein a plurality of tongueelements spaced apart from one another are exposed over a length of theside edge (II).
 7. The method according to claim 1, wherein the outeredge of the tongue element is bevelled at an angle (α) to the top.